Periodic Reporting for period 2 - AEROMO2 (Towards the application of MOrphing MOvables in AEROstructures)
Periodo di rendicontazione: 2022-01-01 al 2023-07-31
(I) a comprehensive flexible element behaviour characterisation and prediction method, specific for the requirements coupled with this application, subsequently called ‘Part A’,
(II) a production method necessary to demonstrate the application of a novel pressurised cell actuation system subsequently called ‘Part B’.
Both parts are complementary, though these will support two types of demontrators. The first part is meant to realise a large step towards qualification of the morphing technology, focussing on materials able to realise large morphing deformation in an existing concept, while the second one focuses on a technology integrating all aspects related to morphing movables, around an innovative fluid based control system, named FAMoUS.
The development to higher TRL of the first concept for morphing movable led to the development of specific test methods to characterise the large deformation behaviour of thermoplastic composite structures. Two structures are used within this concept, i.e. a compliant skin in combination with an hinge based on a deformable structure, having as contradictory characteristic to be bending compliant though shear stiff. The use of thermoplastic composites is supported by its performance tunability, low density and recyclability. Still these materials are usually used for their high stiffness, not for their compliance. The combination of large deformation and repeated loadings asked for the development of test methods on element level in order to describe the limits and the failure behaviour for these structures. Simulating the behaviour of these flexible structure is necessary to provide the industry with the possibility to design these morphing structures for any type of movable and aircraft. It was found in this first period that a test method reproducing the typical deformation patterns leading to failure was necessary. This method used curved coupon specimens was used both under quasi-static conditions as under fatigue conditions to build a material model specific for the type of material used. This material model was then used to provide a new design for a set of requirements meant for a morphing winglet application.
The main objective concerning the second concept, meant to provide a design solution integrating all function necessary for a morphing movable, was to develop a manufacturing technology for the concept. The main principle of the concept relies on a fluid based actuator which when morphing provides the required shape change. Main challenges for the production of this concepts concerned the choice of suitable materials, adhesion between metal and elastomers, as well as the machining of this material combination. The integration of a fibre based strain measurement system was also taken into account for the control of the deformation during morphing. These principles were applied to a single cell and successfully tested, while the coming period will see the design and production of a larger scale multicell system meant as a demonstrator.